The present invention relates generally to electromagnetic energy collection and more particularly to devices useful in the collection and utilization of energy emanating from a source of finite dimension and finite distance from the collection device, wherein the collection device is a nonimaging cylindrical type collector. For example, a secondary solar energy collector is a device which is positioned to receive energy reflected by a primary collector. The primary collector, which is of fixed dimension and fixed distance from the secondary collector can be considered as a source of electromagnetic energy. Prior art secondary collectors have not provided side wall shapes capable of reflecting all incident energy from the primary source onto the body of a smoothly shaped energy absorber, but rather require extended fins and protrusions to capture all of the desired energy. Further, the prior art schemes do not provide a satisfactory solution for secondary collector design where it is desirable to position the secondary collector asymmetrically disposed with respect to the light source.
The inventor, in a prior U.S. application for Radiant Energy Collector, Ser. No. 492,074, filed July 25, 1974, and in a publication, Solar Energy, Vol. 16, No. 2, pages 89-95, (1974) has shown designs for nonimaging collectors. In these disclosures, however, the inventor has been dealing with an energy source, such as the sun, which is considered to be at an infinite distance from the collector so that all light rays incident from the infinite energy source on the collector are considered to be parallel and, further, that the collector itself is assumed to be aligned symmetrically with respect to the envelope containing the incoming rays.
It is therefore an object of this invention to provide a device for efficiently collecting and concentrating radiant energy.
Another object of this invention is to provide a non-imaging energy collection device for collecting energy from a source of finite dimension and finite distance from the collection device.
Another object of this invention is to provide a non-imaging energy collection device positioned asymmetrically with respect to an energy source of finite dimension and finite distance from the collector.